Classification
900 - History & geography
600 - Technology
28
620 - Engineering & allied operations
27
700 - The arts; fine & decorative arts
15
000 - Computer science, information & general works
12
333 - Economics of land & energy
11
330 - Economics
10
363 - Other social problems & services
9
610 - Medicine & health
7
140 - Specific philosophical schools
6
380 - Commerce, communications & transportation
5
551 - Geology, hydrology & meteorology
5
580 - Plants (Botany)
5
658 - General management
5
320 - Political science
4
630 - Agriculture & related technologies
4
300 - Social sciences
3
304 - Factors affecting social behavior
2
340 - Law
2
370 - Education
2
400 - Language
2
414 - Phonology & phonetics
2
500 - Natural sciences & mathematics
2
576 - Genetics & evolution
2
720 - Architecture
2
800 - Literature & rhetoric
2
100 - Philosophy & psychology
1
120 - Epistemology, causation & humankind
1
170 - Ethics
1
200 - Religion
1
297 - Islam, Babism & Bahai Faith
1
301 - Sociology & anthropology
1
410 - Linguistics
1
540 - Chemistry & allied sciences
1
550 - Earth sciences
1
581 - Specific topics in natural history
1
657 - Accounting
1